MG made some changes and we felt it worthwhile to do some testing and
report back on the results. MG Greens proved to be quite an
improvement. The results of the
MG Green Tire Evaluation were
published last May.
Just to refresh our position, we don't have any reason to offer a
biased opinion when we offer a test report. Last year we ran a
report titled "Tire Wars" and tested several brands and hardness grades at
no small cost to see which tire worked best for us. If you want to
see the results you will have to be a subscriber. Or you can spend
$3000 to test for yourself.
MG Yellows are the Spec Tire for the SKUSA 125 and 80cc classes, but
are pretty popular among TAG and Long Track Racers. We first
read some of the forum chatter about the Yellows last March and the
comments were a bit less then positive. Our experience with
the MG Yellows were very positive.
As with the MG Greens, we were told to run 7-8 PSI cold for racing. We ran 10 PSI
for the first heat cycle getting within the suggested range in four 1/2
mile laps - progressively working up speed (135-145°) without sliding.
Then we cooled them with water.
125 Shifter Tire test Conditions & Notes
Testing at the 1/2 mile Denton track, we put 10 laps on the first real
heat cycle. The Yellows just don't have the grip of the Greens
as expected. They feel sort of like a lazy Bridgestone YHB - not
quite the same grip, but close. The margin of reserve was
phenomenal. Pushing the tires a little harder showed they have a
great tolerance to abuse, the kind where you have those 20 lap battles
swapping positions every other lap with someone who's right there.
Except you don't have to back off to cool the tires every 5 laps.
Once they heat up for first real heat cycle, the MG Yellows come on
pretty well. At 7 PSI on a track with a surface temp of 129°
they took about 8-9 laps to really come in. Once they came in they
stayed pretty stable with no signs of overheating or blistering when
pushed in the first real heat cycle. It just seemed that it took too
long to come in at 7 PSI (cold) so we bumped them up to 8 PSI for the rest
of the testing. Our best time in this session was a 37.16, not bad
for a green track.
In the second session we ran 20 laps again at 8 PSI. This time it
only took about 6 laps for the tires to hook up, and they seemed just as
good as in the first 10 lap session. Grip was consistent, and the
margin of reserve still gave the same exceptional confidence level.
Wear was very acceptable. In the last 5 laps the driver turned up
the heat and began to abuse the tires. They held up pretty well but
began to show some signs of compound "complexion" change. You
know how tire tread gets that porous look like an old wind-burned face
that had a bad case of acne in their youth? that same texture yet no
sign of blistering. Best lap time was 37.08
By the third heat cycle the Yellows were beginning to drop off in lap
times while the driver felt they offered the same grip. Data was
showing they were about .2-.4 mph slower in the same turns then in the
previous session. Not a serious degradation in performance but
enough to account for 3/10 slower lap times with the best being 37.42.
In the fourth session we jacked up the tires to 10 PSI Cold, and with
the track temp up to 134° we figured the tire would come earlier.
That they did, with the sweet spot coming in about 4 laps. Un
fortunately lap times began to fall away after about 8 laps. By the
time we got to about lap 25 (65 laps total) lap times were up to 37.80's.
We stopped the test at a grand total of 72 laps.
In previous years we noticed the MG tires in general had a tendency to
decompose on really hot days at long tracks. At the IKF Long Track
Nationals held at Oak Hill under the hotter then normal June Texas
weather, not one of the new MG tires had a problem. I'm satisfied
they've cured the earlier high-temp problems with the newer compounds.
The earlier MG Yellows were famous for having a long life with
consistent performance. The new tires also maintain a long life but
there is a little difference; The performance edge seems to be after
the first competition heat cycle rather then in the first performance heat
cycle. Like any tire once they've hit a point where the volatiles
have boiled away from a solid overheating cycle, the tires tend to drop
off, the new Yellows more quickly then the old. Problems that some
people were reporting with the tires fading after 10 laps are almost
certainly attributed to excess pressure. The Yellows worked best on
a 125 Shifter at 8PSI cold.
Comments from TAG driver Sean Owens
We noticed Sean Owens was running the MG Yellows at the KART
Nationals held at Denton TX this year and asked him to provide us with his
When I raced on the MG yellows in the 2005 KART
sprint nationals at North Texas Karters in Denton Texas I was shocked on
how responsive the kart was. I just set the tire pressures the same as I
had set them with the MO JO’s and right off the bat the lap times I was
turning “38.2’s with the MO JO’s” turned into 37.2’s. (You can see my
lap times at
tires felt like they had a huge margin for error, I could take the kart
into the corner a little hotter than normal and the kart would come back
to me very easily. Also, the kart responded very nicely on turn in, I
would just point the kart where I wanted it and it would go there.
Another thing I noticed on the MG yellows is the tire never went away
during the race; they remained consistent from lap 1 until the last lap
of the race.
From now on when I have a chance to race between
tires in a TAG race I am going to choose the MG yellows because they
have more bite than Bridgestone YHC’s and are also softer than the
Bridgestone YGK’s and they definitely have more bite and flex than the
new MO JO tire.
While the MG Yellows are typically classified in the same group as the
popular Bridgestone YHC, they offer an excellent combination of grip,
wear, and drivability. We would strongly recommend these tires in
any series that specifies a harder compound or even a specific tire.